CN116035538B - Multimodal imaging system, working method and use for assessing tissue oxygenation status - Google Patents

Abstract

The invention discloses a multimodal imaging system, working method and application for evaluating tissue oxygenation state. The system includes: a test object acquisition module, a basic data measurement module, a gray-scale ultrasound module, a photoacoustic imaging module, a plane wave imaging module, and a calculation module , the statistical analysis module. The present invention obtains the structural information, oxygenation state data, and blood vessel density information of the placenta of pregnant rats, calculates the diagnostic ability AUC of the receiver operating characteristic ROC in the diagnostic mode by a standard method, and performs statistical analysis, which can be real-time and non-invasive. Evaluate tissue oxygenation status, and the evaluation results are more accurate.

Description

Multimodal imaging system, working method and use for assessing tissue oxygenation status

technical field

The present invention relates to the technical field of medical image processing, in particular to a multimodal imaging system for evaluating tissue oxygenation status, and the working method and application of the system, which is mainly used for gray-scale ultrasonic imaging, photoacoustic imaging and plane wave imaging image processing.

Background technique

Preeclampsia is one of the most common complications of pregnancy and can rapidly develop with serious consequences including maternal and fetal death. The current diagnosis of preeclampsia relies on clinical findings, including hypertension and proteinuria at 20 weeks' gestation and/or < 48 hours after delivery. However, once hypertension occurs, preeclampsia can rapidly deteriorate into a life-threatening hypertensive crisis for pregnant women. Since the clinical manifestations cannot be diagnosed timely and accurately, there is an urgent need to develop more accurate, sensitive, and non-invasive diagnostic indicators for preeclampsia.

Photoacoustic imaging is an emerging imaging technique that can image common endogenous chromophores, including water, oxygenated hemoglobin (HbO ₂ ), deoxygenated hemoglobin (Hb), melanin, and lipids. Due to its ultrasonic and optical properties, this method can simultaneously evaluate the chemical composition and tissue structural characteristics of tissues, and has the advantages of high resolution and non-invasiveness. Relying on its strength, photoacoustic imaging has developed rapidly in recent years and has been widely used in the fields of brain, thyroid, breast, skin, lymphatic system, gynecology, urological imaging, intraoperative imaging, etc. The ability of photoacoustic imaging to evaluate tissue oxygenation status has become Get confirmed. In addition, the oxygenation capacity of the placenta is not only determined by the oxygenation state of the placenta, but also closely related to the state of placental neovascularization. Therefore, information about placental vascularization will help to further improve the accuracy of diagnosis.

Plane wave imaging is a microvascular blood flow imaging method based on unfocused wave imaging technology. Benefiting from a fast processing platform and efficient wall filtering algorithms, plane wave imaging distinguishes blood flow signals from low-speed tissue motion and demonstrates the ability to visualize microvascular morphology. Compared with power Doppler, plane-wave imaging at 32 weeks of gestation more clearly visualized small blood vessels within the placenta, even in the presence of maternal respiratory motion. Therefore, plane wave imaging has advantages in early diagnosis of placental neovascularization. In preeclampsia, extravasation of the superficial trophoblast leads to incomplete remodeling of maternal spiral vessels, resulting in hyperresistive, low-volume vessels and vascular smooth muscle histopathology affecting placental angiogenesis, so the use of plane wave imaging to assess placental blood perfusion and distribution will Aids in early diagnosis of preeclampsia.

Although the above-mentioned imaging methods can provide important information of the placenta in real time and non-invasively, the current single imaging method can only provide limited structural or functional information, and cannot perform a more comprehensive evaluation of the placenta. The multimodal imaging method integrating gray-scale ultrasound, photoacoustic imaging and plane wave imaging and other imaging technologies can provide morphological and functional information at the same time.

Contents of the invention

In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a multi-modal imaging system for assessing tissue oxygenation status, which combines traditional ultrasonic gray-scale imaging, photoacoustic imaging and plane wave imaging. Structural and functional multi-parameter imaging of the placenta enables real-time and non-invasive assessment of tissue oxygenation status with more accurate assessment results.

The technical solution of the present invention is: the multimodal imaging system for evaluating tissue oxygenation status, which includes:

A test object acquisition module configured to randomly divide pregnant rats into a hypoxia group and a normoxia group, wherein the oxygen concentration of the hypoxia group is 12 ± 2%, and the oxygen concentration of the normoxia group is 20 ± 2%;

A basic data measurement module configured to measure blood pressure, proteinuria and fetal mass on day 18 of pregnancy;

A gray-scale ultrasound module configured to obtain placental structure information provided by gray-scale ultrasound on the 18th day of pregnancy;

A photoacoustic imaging module configured to obtain oxygenation status data of the placenta of the rat on the 18th day of pregnancy;

a plane wave imaging module configured to image vessel density in cross-sections at the umbilical cord placental entrance of each placenta of the rat on day 18 of gestation;

a calculation module configured to calculate the diagnostic capability AUC of the receiver operating characteristic ROC of the diagnostic mode using standard methods;

The statistical analysis module is configured to perform statistical analysis on the data of the gray-scale ultrasound module, the photoacoustic imaging module, and the plane wave imaging module.

The present invention obtains the structural information, oxygenation state data, and blood vessel density information of the placenta of pregnant rats, calculates the diagnostic ability AUC of the receiver operating characteristic ROC in the diagnostic mode by a standard method, and performs statistical analysis, which can be real-time and non-invasive. Evaluate tissue oxygen saturation, and the evaluation results are more accurate.

Also provided is a method of operation of a multimodal imaging system for assessing tissue oxygen saturation comprising the steps of:

(1) The pregnant rats were randomly divided into the hypoxia group and the normoxia group, the oxygen concentration in the hypoxia group was 12±2%, and the oxygen concentration in the normoxia group was 20±2%;

(2) Blood pressure, proteinuria and fetal mass were measured on the 18th day of pregnancy;

(3) Obtain placental structure data on the 18th day of pregnancy;

(4) On the 18th day of pregnancy, obtain the oxygenation status data of the placenta of the rat;

(5) On the 18th day of pregnancy, imaging was performed on the transverse section of the umbilical cord placental entrance of each placenta of the rat to obtain the blood vessel density;

(6) Calculate the AUC of the receiver operating characteristic ROC in diagnostic mode using standard methods;

(7) Perform statistical analysis on the data of steps (3)-(5) (namely placental structure information, placental oxygenation status data, blood vessel density).

Also provided is the use of this multimodal imaging system for assessing tissue oxygenation status for diagnosing pre-eclampsia and providing dynamic monitoring in the treatment of pre-eclampsia.

Description of drawings

FIG. 1 is a flowchart of a multimodal imaging system for assessing tissue oxygenation status according to the present invention.

Detailed ways

This multimodal imaging system for assessing tissue oxygenation status includes:

A test object acquisition module configured to randomly divide pregnant rats into a hypoxia group and a normoxia group, wherein the oxygen concentration of the hypoxia group is 12 ± 2%, and the oxygen concentration of the normoxia group is 20 ± 2%;

A basic data measurement module configured to measure blood pressure, proteinuria and fetal mass on day 18 of pregnancy;

A gray-scale ultrasound module configured to obtain placental structure information provided by gray-scale ultrasound on the 18th day of pregnancy;

A photoacoustic imaging module configured to obtain oxygenation status data of the placenta of the rat on the 18th day of pregnancy;

a plane wave imaging module configured to image vessel density in cross-sections at the umbilical cord placental entrance of each placenta of the rat on day 18 of gestation;

a calculation module configured to calculate the diagnostic capability AUC of the receiver operating characteristic ROC of the diagnostic mode using standard methods;

The statistical analysis module is configured to perform statistical analysis on the data of the gray-scale ultrasound module, the photoacoustic imaging module, and the plane wave imaging module.

The present invention obtains the structural data, oxygenation state data, and blood vessel density information of the placenta of pregnant rats, uses standard methods to calculate the diagnostic ability AUC of the receiver operating characteristic ROC in the diagnostic mode, and performs statistical analysis to achieve real-time and non-invasive Evaluate tissue oxygenation status, and the evaluation results are more accurate.

Preferably, the gray-scale ultrasound module uses a 20 MHz probe to identify the reproductive system of pregnant mice. The cervix of the pregnant mouse is displayed on the cross section of the lower abdomen of the pregnant mouse. After the image is displayed clearly, turn the probe to adjust to the direction along the long axis of the left uterine horn to display the first gestational sac on the lower left along the uterine horn. Adjust the depth and focus of the probe. Make the fetal mouse and placenta in the target gestational sac clearly displayed; scan the fetal mouse and placenta continuously to observe their shape and position relationship; measure and record their length in the mid-sagittal section of the fetal mouse, and display the complete placental shape at the entrance of the umbilical cord placenta to outline the placenta The circumference and area were recorded; then, follow the shape of the left uterine horn, locate the last gestational sac on the upper left side, and repeat the above observation and measurement operations; the first gestational sac and the right uterine For the last gestational sac in the upper right corner, perform the same operation as above; collect four target gestational sacs in the lower left, upper left, lower right, and upper right of each pregnant mouse; all measured values should be measured three times, and the average value should be taken.

Preferably, the photoacoustic imaging module places a guide pad on the abdomen of the pregnant mouse, uses a 9 MHz photoacoustic-ultrasound probe to display the cervix of the pregnant mouse in a cross-section of the lower abdomen of the pregnant mouse, and then rotates the probe to adjust to the direction along the long axis of the left uterine horn , to display the first gestational sac on the lower left along the uterine horn, adjust the depth and focus of the probe, so that the fetus and placenta in the target gestational sac can be clearly displayed; switch the probe to the photoacoustic mode at the largest sagittal section of the placenta, and adjust the photoacoustic imaging range , so that it includes the placenta, but does not exceed the largest long diameter of the placenta; observe the distribution of photoacoustic signals, calculate and record its oxygenation status; then, follow the shape of the left uterine horn, locate the last gestational sac on the upper left side, and repeat the above Observation and measurement operations; perform the same operation on the first gestational sac at the lower right of the right uterine horn and the last gestational sac at the upper right of the right uterine horn. A total of four target gestational sacs were collected from each pregnant mouse; all measured values should be measured three times, and the average value was taken.

Preferably, the plane wave imaging module displays the cervix of the pregnant mouse in the cross-section of the lower abdomen of the pregnant mouse. After the image is displayed clearly, the probe is rotated to adjust to the direction along the long axis of the left uterine horn, and the first pregnancy on the lower left side along the uterine horn is displayed. sac, adjust the depth and focus of the probe, so that the fetal mouse and placenta in the target gestational sac are clearly displayed; display the largest coronal section of the placenta passing through the umbilical cord placental entrance, switch the probe to plane wave mode, adjust the speed scale to 4.5cm/s, and set the gain to 50dB; observe Microvascular structure and color signal distribution, after the image is stable, outline each target placenta, calculate the area of the placenta and the area of blood vessels displayed by the plane wave, respectively, and divide the area of the plane wave blood vessels by the area of the placenta to obtain the blood vessel density of the placenta Then, follow the shape of the left uterine horn, locate the last gestational sac on the upper left side, repeat the above observation and measurement operations; Carry out the same operation for the gestational sac according to the above steps; collect four target gestational sacs in the lower left, upper left, lower right, and upper right of each pregnant mouse; all measured values should be measured three times, and the average value should be taken.

Preferably, the statistical analysis module performs statistical analysis on the data of the gray-scale ultrasound module, the photoacoustic imaging module, and the plane wave imaging module.

As shown in Figure 1, a working method of a multimodal imaging system for assessing tissue oxygenation status is also provided, which includes the following steps:

(1) The pregnant rats were randomly divided into the hypoxia group and the normoxia group, the oxygen concentration in the hypoxia group was 12±2%, and the oxygen concentration in the normoxia group was 20±2%;

(2) Blood pressure, proteinuria and fetal mass were measured on the 18th day of pregnancy;

(3) Obtain placental structure data on the 18th day of pregnancy;

(4) On the 18th day of pregnancy, obtain the oxygenation status data of the placenta of the rat;

(5) On the 18th day of pregnancy, imaging was performed on the transverse section of the umbilical cord placental entrance of each placenta of the rat to obtain the blood vessel density;

(6) Calculate the AUC of the receiver operating characteristic ROC in diagnostic mode using standard methods;

(7) Perform statistical analysis on the data from steps (3)-(5).

Also provided is the use of this multimodal imaging system for assessing tissue oxygenation status for diagnosing pre-eclampsia and providing dynamic monitoring in the treatment of pre-eclampsia.

The results showed that the multimodal imaging system was effective in the diagnosis of preeclampsia, and the AUC of the model reached 0.82, indicating that the multimodal imaging system has application value in the auxiliary diagnosis of preeclampsia. The multimodal imaging system strategy used in this experiment may also provide new ideas for accurate diagnosis of other diseases.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are still within the scope of this invention. The protection scope of the technical solution of the invention.

Claims (8)

1. A multi-modality imaging system for assessing oxygenation status of tissue, characterized by: it comprises the following steps:

a test subject acquisition module configured to randomly divide pregnant rats into an anoxic group and an normoxic group, wherein the anoxic group has an oxygen concentration of 12±2% and the normoxic group has an oxygen concentration of 20±2%;

a basal data measurement module configured to measure blood pressure, proteinuria and fetal mass at day 18 of gestation;

the gray-scale ultrasonic module is configured to acquire placenta structure information provided by gray-scale ultrasonic on the 18 th day of pregnancy;

a photoacoustic imaging module configured to acquire placental oxygenation status data of a rat on day 18 of gestation;

a plane wave imaging module configured to image on day 18 of gestation on a cross-section at the umbilical placenta entrance of each placenta of the rat to obtain a vascular density;

a calculation module configured to calculate a diagnostic capacity AUC of a receiver operating characteristic ROC of the diagnostic mode using standard methods;

and the statistical analysis module is configured to perform statistical analysis on the data of the gray-scale ultrasonic module, the photoacoustic imaging module and the plane wave imaging module.

2. The multi-modality imaging system for assessing the oxygenation status of tissue of claim 1, wherein: the gray-scale ultrasonic module uses a 20 MHz probe to identify the reproductive system of a pregnant mouse; displaying the cervix uteri of the pregnant mouse on the cross section of the lower abdomen of the pregnant mouse, after the image display is clear, rotating the probe to be adjusted to be along the long axis direction of the left uterine angle, displaying the first gestational sac at the lower left along the uterine angle, and adjusting the depth and the focus of the probe to enable the target gestational sac inner tube mouse and placenta to be clearly displayed; continuously scanning the fetal mice and placenta, and observing the morphology and the position relationship of the fetal mice and placenta; measuring the length of the placenta from a median sagittal section of a fetal mouse, recording, displaying the shape of the complete placenta at an umbilical placenta entrance, outlining the perimeter and the area of the placenta, and recording; then, the left upper last gestational sac is positioned along the left uterine horn shape, and the observation and measurement operations are repeated; the same operation is carried out on the first gestational sac at the right lower uterine horn and the last gestational sac at the right upper uterine horn according to the steps; four target gestational sacs on the left lower part, the left upper part, the right lower part and the right upper part are collected by each gestational mouse; all measurements were taken three times and averaged.

3. The multi-modality imaging system for assessing the oxygenation status of tissue of claim 2, wherein: the photoacoustic imaging module is used for placing a guide pad on the abdomen of a pregnant mouse, and after the cervical of the pregnant mouse is displayed on the cross section of the lower abdomen of the pregnant mouse by using a 9 MHz photoacoustic-ultrasonic probe, the probe is rotated to be adjusted to be along the long axis direction of the left uterine angle, and the first pregnancy sac which appears along the uterine angle and is left and lower is displayed; the depth and focus of the probe are regulated, so that the target pregnant inner tube mice and placenta are clearly displayed; switching the probe to a photoacoustic mode in the maximum sagittal section of the placenta, and adjusting the photoacoustic imaging range to contain the placenta but not exceed the maximum diameter of the placenta; observing the distribution of the photoacoustic signals, and calculating and recording the oxygenation state of the photoacoustic signals; subsequently, the left upper last gestational sac is positioned along the left uterine horn; repeating the above observation and measurement operations; the same operation is carried out on the first gestational sac at the right lower uterine horn and the last gestational sac at the right upper uterine horn according to the steps; four target gestational sacs on the left lower part, the left upper part, the right lower part and the right upper part are collected by each gestational mouse; all measurements should be taken three times and averaged.

4. The multi-modality imaging system for assessing the oxygenation status of tissue of claim 3 wherein: the plane wave imaging module displays the cervix uteri of the pregnant mouse on the cross section of the lower abdomen of the pregnant mouse, after the image is displayed clearly, the probe is rotated to be adjusted to be along the long axis direction of the left uterine angle, the first gestational sac at the lower left along the uterine angle is displayed, and the depth and the focus of the probe are adjusted to enable the target gestational sac inner tube mouse and placenta to be displayed clearly; the maximum coronal section of the placenta passing through the umbilical placenta entrance is displayed, the probe is switched to a plane wave mode, the speed scale is adjusted to 4.5cm/s, and the gain is set to be 50dB; observing the fine vascular structure and color signal distribution, after the image is stable, outlining each target placenta, respectively calculating the area of the placenta with the section and the area of the blood vessel displayed by the plane wave, and dividing the area of the blood vessel with the plane wave by the area of the placenta to obtain the blood vessel density of the placenta; then, the left upper last gestational sac is positioned along the left uterine horn shape, and the observation and measurement operations are repeated; the same operation is carried out on the first gestational sac at the right lower uterine horn and the last gestational sac at the right upper uterine horn according to the steps; four target gestational sacs on the left lower part, the left upper part, the right lower part and the right upper part are collected by each gestational mouse; all measurements should be taken three times and averaged.

5. The multi-modality imaging system for assessing the oxygenation status of tissue of claim 4 wherein: the calculation module calculates the diagnostic capacity AUC of the receiver operating characteristic ROC of the diagnostic mode according to standard methods.

6. The multi-modality imaging system for assessing the oxygenation status of tissue of claim 5, wherein: and the statistical analysis module performs statistical analysis according to the data of the gray-scale ultrasonic module, the photoacoustic imaging module and the plane wave imaging module.

7. The method of operating a multi-modality imaging system for assessing the oxygenation status of tissue of claim 1, wherein: which comprises the following steps:

(1) The pregnant rats are randomly divided into an anoxic group and an normoxic group, wherein the oxygen concentration of the anoxic group is 12+/-2%, and the oxygen concentration of the normoxic group is 20+/-2%;

(2) Blood pressure, proteinuria and fetal mass were measured on day 18 of gestation;

(3) At day 18 of gestation, placenta structure information is obtained;

(4) On day 18 of gestation, oxygenation status data of the placenta of the rat is obtained;

(5) On day 18 of gestation, imaging was performed on a cross section at the umbilical placenta entrance of each placenta of the rat to obtain vascular density;

(6) Calculating an AUC of a receiver operating characteristic ROC of the diagnostic mode using standard methods;

(7) And (3) carrying out statistical analysis on the data in the steps (3) - (5).

8. Use of a multi-modality imaging system for assessing the oxygenation status of tissue of claim 1, wherein: which is used to diagnose pre-eclampsia and provides dynamic monitoring in the treatment of pre-eclampsia.

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